In the event of traffic accidents, in particular with tail-end impact accidents of motor vehicles, there is the danger that the vehicle seat due to the arising forces performs a backwards downward movement, that is, in the direction of the rear of the vehicle and vehicle floor with respect to the installation position of the vehicle seat in a vehicle. As a result, there is a specific danger for the persons present in the vehicle. On the one hand there is the danger that the vehicle seat is loosened at least partially from the seat rail system or that the latter is deformed, whereby the uncontrolled movements of the vehicle seat caused thereby endanger the person present on the vehicle seat and others present in the vehicle. In addition, there is a displacement of the person located on the vehicle seat, such that the safety systems, for instance airbag and seatbelt, can no longer optimally fulfill the function thereof.
A few devices are known from the prior art which effect a stabilization of a vehicle seat on a pair of seat rails and should prevent a backward displacement of the vehicle seat in the event of a crash. All known devices are based on different, in each case, highly complex mechanisms having several movable components, wherein a movement sequence of these components is typically triggered by mechanical or electronic signals which leads to a locking or fastening of the vehicle seat at the vehicle structure or at a pair of seat rails supporting the seat.
An essential disadvantage of these devices lies in the necessity of triggering those mechanisms by external signals, the complexity of the mechanisms and of the movable components of the locking mechanisms, because the movement thereof leads on the one hand to a certain time delay of the locking of the vehicle seat after an accident triggering the mechanism, and on the other hand with increasing complexity of the mechanisms the failure rate increases and the reliability correspondingly decreases.